Harley-Davidson Inc., known for gasoline-powered motorcycles thundering with machismo, is testing a battery-powered model that it hopes will appeal to younger people concerned about the environment.

"We'd like to get customer feedback," Matt Levatich, Harley's president and chief operating officer, said in an interview, adding that the product is at least two years away from being offered for sale. For now, he said, the lithium-ion batteries in prototype models have a range of roughly 100 miles between...